Sack filling apparatus

ABSTRACT

APPARATUS FOR THE AUTOMATIC FILLING AND SEALING OF SACKS, INCLUDING SUCTION PICK-UP MEANS FOR LIFTING THE SACKS ONE BY ONE FROM A STACK, FURTHER SUCTION MEANS COOPERABLE WITH THE PICK-UP MEANS TO OPEN THE SACK MOUTH WITH THE SACK HELD AT ITS TOP CORNERS BY GRIPPERS MOUNTED ON A HORIZONTALLY MOVABLE CARRIAGE, A FILLING SPOUT MOUNTED ON THE CARRIAGE AND LOWERABLE INTO THE OPEN MOUTH OF THE SACK, MEANS FOR TRAVERSING THE CARRIAGE CARRYING THE SACK TO A FILLING STATION WHERE THE FILLING SPOUT IS ALIGNED WITH THE OUTLET FROM A HOPPER, A VIBRATORY POSSER PLATFORM FOR AGITATING THE SACK WHILST IT IS BEING FILLED, AND COOPERATING PAIRS OF CHAIN DRIVES FOR GRIPPING THE CLOSED MOUTH   OF THE FILLED SACK AND TRANSVERSING IT ON A CONVEYOR TO A MOUTH SEALING STATION.

:March 2, 1971 J. c. THORNE AL SACK FILLING APPARATUS 4 Sheets-Sheet 1 Filed June 5, 1 968 //VVENTOP$ Joy/v 6. Fla /v5 7 Johw L. Mano/ms Jo /v H FISHER PHIL/P M. #ommvs FRANK A. N2 IVA/#4 BY DONALD E F/LMER m ATTORNEYS March 2, 1971 J THQRNE ETAL 3,566,578

SACK FILLING APPARATUS 4 Sheets-Sheet 2 Filed June 5. 1968 /7 y; Jay/v L. Mann/m5 5 fm m6 3. N H 07 m, A W. o 4 H n 0 2 79 42 7 1 g) 4 United States Patent 3,566,578 SACK FILLING APPARATUS John C. Thorne, Maidstone, John L. Maddams, Rochester, John H. Fisher, Maidstone, Philip M. Hargrave, Rochester, and Frank R. Newnham and Donald F. Filmer, Maidstone, England, assignors to Reed Paper Group Limited, London, England Filed June 3, 1968, Ser. No. 734,068 Claims priority, application Great Britain, June 9, 1967, 26,846/ 67 Int. Cl. B65b 43/30 US. Cl. 53-126 20 Claims ABSTRACT OF THE DISCLOSURE Apparatus for the automatic filling and sealing of sacks, including suction pick-up means for lifting the sacks one by one from a stack, further suction means cooperable with the pick-up means to open the sack mouth with the sack held at its top corners by grippers mounted on a horizontally movable carriage, a filling spout mounted on the carriage and lowerable into the open mouth of the sack, means for traversing the carriage carrying the sack to a filling statiOn where the filling spout is aligned with the outlet from a hopper, a vibratory posser platform for agitating the sack whilst it is being filled, and cooperating pairs of chain drives for gripping the closed mouth of the filled sack and traversing it on a conveyor to a mouth sealing station.

This invention relates to the filling of flexible sacks, bags and like containers made of non-woven sheet material, and has as its primary object to provide improved apparatus for handling sacks and bags during filling which apparatus requires only slight supervision and which is therefore economical in manpower.

Thus viewed from a broad aspect the invention provides apparatus for use in the filling of flexible sacks or bags, such apparatus comprising lifting means operable to lift a sack or bag and to present the same to a filling spout, suction means operable to open the mouth of the sack or bag, and means operable to bring about relative movement between the open sack or bag and the filling spout to engage the sack or bag with the spout for filling.

The said suction means may conveniently comprise a pair of suction devices adapted to engage the sack or bag on opposite sides thereof in the region of its mouth and movable relatively to one another to draw the mouth open for engagement with the said filling spout. Clearly the relative movement which is then brought about between the sack or bag and the filling spout may be by movement of either or both of such elements; in a preferred form of the invention the filling spout is mounted for movement into and out of the open mouth of the stationary sack or bag.

Very conveniently, and in accordance with an important preferred feature of the invention, one of the said suction devices may be associated with the said means for lifting a sack or bag to present it to the filler spout, so as to constitute the means whereby the said lifting means grips the sack or bag to lift it. The other suction device will then be mounted so as to be engageable with the sack or bag on the side thereof opposite from that where it is already gripped by the first-mentioned suction device, once the sack or bag has been lifted. The association of such a suction device with the lifting means provides a convenient means of enabling the sack or bag to be gripped for lifting, and in particular enables the topmost sack or bag of a stack thereof to be gripped and lifted without difiiculty, thus permitting a very simple 3,566,578 Patented Mar. 2, 1971 mode of presentation of a store of sacks or bags to the lifting means in the form of such a stack.

In a preferred form of the invention the sacks or bags are supplied to the lifting means in stacks on an endless conveyor and the lifting means comprises an arm carrying a suction device and swingable about a pivotal mounting to pick up sacks or bags one by one from the top of such a stack and lift them.

Each of the said suction devices may comprise one or more suction cups, and the suction cups of the respective suction devices will preferably co-operate in one or more pairs of axially aligned suction cups so as to achieve a symmetrical opening of the mouth of the sack or bag. Thus in a simple form of the invention each of said suction devices comprises a single suction cup, the arrangement being such that said cups are disposed on a common axis and positioned to engage the mouth of a sack or bag substantially centrally of its width when in their relative positions for opening the mouth of the sack or bag.

In an alternative arrangement however, which is preferable in many circumstances, each of said suction devices comprises two or more suction cups, the arrangement being such that the cups of the two devices are disposed in axially aligned co-operating pairs when in their relative positions for opening the mouth of a sack or bag. Preferably each of said suction devices comprises three suction cups, the central co-operating pair of cups being arranged to engage the mouth of a sack or bag substantially centrally of its width whilst the two outer co-operating pairs of cups are arranged to engage the mouth of a sack or bag one on each side of said central co-operating pair.

When each of the suction devices comprises three suction cups as aforesaid it is desirable that the cups of each device should be movable relative to one another as the mouth of a sack or bag is opened thereby, so as to cause such mouth to be opened to a substantially circular or oval configuration rather than a rectangular one, it being understood that when they first engage the sack or bag mouth the suction cups of each device must have their mouths aligned in a common plane. Preferably, therefore, the two outer cups of each suction device are connected to the central cup thereof via flexible connections which connections may conveniently include one or more flexible mounting plates for the outer suction cups. said flexible plate or plates extending outwardly beyond said outer suction cups and being engageable with stop members of the apparatus when the two suction devices are moved relative to one another to open the mouth of a sack or bag, so as by flexure of said mounting plates to cause the sack or bag mouth to be opened to a substantially circular or oval configuration.

The apparatus of the invention is intended to find particular utility in the filling of sacks or bags made of plastics sheet material, which is of course highly flexible and as a result diflicult to handle in some respects. Preferably therefore a guide shoe will be provided to receive the mouth of the sack or bag as it is lifted into the mouth opening region, such guide shoe being arranged to define the position of the mouth of the sack or bag for opening by the said suction means.

It is desirable that the attitude of the open mouth of the sack or bag during the filling step should be accurately defined, and this may not be possible simply by the employment of the said suction means to hold the mouth open. Preferably, therefore, the apparatus includes a pair of mechanical gripper devices operable to grip the sack or bag adjacent its mouth at two substantially opposite regions thereof once the sack or bag has been lifted by said lifting means, such gripper devices being movable towards and away from one another so as, respectively,

to enable the mouth of the sack or bag to be opened by the said suction means and to close the same once it has filled; in other words relative movement of the grippers towards one another accommodates opening of the mouth of the sack or bag whilst subsequent separating movement of the grippers closes it again.

Although the said filling spout may if desired be secured to or movably mounted on the outlet from a storage hopper for the commodity concerned, we prefer to provide the filling sput as part of the apparatus of the invention and in a preferred embodiment it is mounted in a common assembly with the above-mentioned gripper devices, the filling spout being movable relatively to the gripping devices so as to be insertable in and withdrawable from the open mouth of a sack or bag held by such devices.

In a preferred form of the invention the said filling spout and gripper devices are mounted on a carriage which is movable between a sack or bag receiving and opening station in which the sack or bag is received from the said lifting means, has its mouth opened by the said suction means, and is engaged with the said filling spout, but at which station the said spout is displaced from the outlet from a storage hopper or other container for the commodity concerned, and a sack or bag filling station in which the said filling spout is aligned with the outlet from such a hopper for the passage of material into the sack or bag via the spout. The said suction means for opening the mouth of the sack or bag, or that one of the two suction devices which is not associated with the lifting means in the preferred form of the invention already referred to, may then be permanently situated at the said sack or bag receiving and opening station, as once the mouth of the sack or bag has been gripped by the gripper devices, opened, and engaged with the filling spout, it will be held open for filling without any further assistance being required from said suction means.

During filling of the sack or bag with many kinds of commodity, and in particular granular or comminuted solids, it will be necessary to agitate or poss the sack or bag and complete filling thereof. Preferably, therefore, the apparatus of the invention includes a vibratory posser situated so that the sack or bag will sit on a vibrating platform thereof whilst it is being filled. Clearly, when such a posser is provided in the preferred form of the apparatus referred to above, such posser will be situated at the sack or bag filling station so that the sack or bag will sit thereon during filling. As the sack or bag is filled the tendency will be for its breadth to expand and its depth to contract, and the posser will therefore be mounted for vertical movement so that it may be caused to rise and thus lift the bottom of the sack or bag during filling so as to accommodate such changes in the shape of the sack or bag.

A novel preferred feature of a posser which may advantageously be incorporated in apparatus of the invention is that its vibratory platform may take the form of an endless conveyor. Such conveyor will not of course be operated whilst the sack or bag is being filled, but once filling is complete and the sack or bag is to be moved away from the filling station the conveyor will be operated to assist in such transfer.

The apparatus of the invention preferably includes means for sealing the mouth of the sack or bag once it has been filled, and such means may conveniently take the form of a sewing mechanism of conventional type, or a heat sealer in the case of sacks or bags of plastics sheet material. The apparatus may, however, include novel and advantageous means for transferring the filled sack or bag to such mouth sealing means, in the form of a pair of endless chain drives arranged to co-operate to grip theclosed but unsealed mouth of the sack or bag therebetween to effect such transfer. In the preferred form of the apparatus already referred to such endless chains extend into the sack or bag filling station and are mounted for opening and closing movement relative to one another so as to be open during the filling step but to be closable together to grip the sack or bag mouth therebetween once it has been filled and to draw the sack or bag away for sealing thereof. In a preferred form at least one further pair of endless chain drives are provided downstream of those already mentioned to take over the movement of the sack or bag through the mouth sealing means; such further chain drives need not, of course, be relatively openable and closeable.

Preferably endless conveyor means will be provided on which the sack or bag Will sit throughout its movement through the apparatus after filling; such conveyor means will receive the filled sack or bag from the conveyor associated with the posser where such is provided. It is indeed desirable that suitable underneath support should be provided for the sack or bag throughout its passage through the apparatus once filling has commenced, rather than permitting the sack or bag to be suspended from the aforementioned gripper devices or endless chain drives for example; this is of particular importance when the mouth of the sack or bag is to be sealed by sewing, as the position in which the mouth is presented to the sewing mechanism must then be accurately defined and this will be diflicult if the weight of the filled sack or bag has to be supported via its mouth as it is being transferred to the sewing mechanism.

The various elements of the apparatus of the invention may be powered in any suitable manner, e.g. electrically, hydraulically, pneumatically or mechanically. The interrelation of the movements of such elements to carry a sack or bag through the apparatus may conveniently be achieved by means of micro-switches actuated by the movements of such elements and operative to initiate subsequent operations.

In order that the invention may be readily understood one embodiment of the same, together with a modification thereof, will now be described by way of example and with reference to the accompanying diagrammatic drawings, in which:

FIG. 1 is an end elevation of the apparatus, looking downstream relative to the direction of the movement of sacks or bags therethrough during filling;

FIG. 2 is a plan view of the apparatus with certain parts not shown for the sake of clarity;

FIG. 3 is a view similar to FIG. 2 but with certain parts in different positions and also showing the elements of a sewing mechanism;

FIG. 4 is a view in elevation looking upstream from the plane indicated at IVIV in FIG. 3;

FIG. 5 is a side elevation, again with certain parts removed for the sake of clarity, looking from the left hand side of the apparatus as seen in FIG. 1;

FIG. 6 is a plan view of an alternative arrangement of suction means for opening the mouth of a sack or bag for filling, with the parts in one position; and

FIG. 7 is a view similar to FIG. 6 but with the parts in another position.

The various parts of the apparatus Will be described in the order in which they operate on a sack or bag passing therethrough.

Thus referring first to FIG. 1 the apparatusincludes sack or bag lifting means comprising a support structure 1 carrying a swinging arm 2 mounted at 3 for pivotal movement in a vertical plane at right angles to the length of the apparatus. The arm 2 carries a pneumatic jack 4 whose rod carries a further pneumatic jack 5 whose rod in turn carries a suction device in the form of a rubber cup '6. The arm 2 is swingable by means of a further jack 7 carried on the support structure 1 with its rod linked to the arm 2.

Sacks or bags for filling are delivered to the lifting means in successive stacks 8 on the canted surface of an endless conveyor 9. The illustrated apparatus is particularly intended for use in the filling of paper sacks and the further description will therefore refer to sacks of this kind where appropriate.

The lifting means is shown in its lowered position in full lines in FIG. 1 and in its raised position in dot and dash lines. It will be observed that the jack 4 is operable to extend the suction cup 6 to pick up a sack from the stack thereof. The jack on the other hand is operable to withdraw the suction cup when the mouth of the sack is to be opened as is explained below.

The lifting means is operative to lift a sack, in flat condition and with its mouth upwards, so that its mouth enters a guide shoe 10 (FIG. 1). The guide shoe is stationarily mounted on a main support framework 11 of the apparatus, on which is also carried a second suction device in the form of a suction cup 12 similar to the cup 6. The suction cup 12 is mounted on the rod of a pneumatic jack 13 so as to be movable towards and away from the guide shoe 10.

The two top horizontal members 14 of the supporting framework 11 are formed as runners and mount a carriage 15 for movement therealong lengthwise of the apparatus. The carriage carries a filling spout 16 and two gripper devices each of which devices consists of a fixedly mounted gripper member 17 and a movable gripper member 18 (see FIG. 4 in particular).

The filling spout 16 is mounted for vertical axial movement in the carriage 15. Thus the spout is carried by a pair of pivotal arms 19 mounted on a side member of the carriage frame and such arms are pivotable by a pneumatic jack 20 on the carriage via a link 21 so as to raise and lower the filling spout as desired, the raised position 'being shown in dot and dash lines in FIG. 4.

The movable gripper members 18 are movable in concert by means of a pneumatic jack 22, to whose rod the grippers 18 are connected, so that the two gripper devices may be opened and closed simultaneously with each other. Moreover, the two gripper devices are mounted for pivotal movement towards and away from one another in directions lengthwise of the apparatus under the influence of a pneumatic jack 23 (FIG. 5) acting through a bellcrank lever 24 and links 25. It will be seen that expansion of the jack 23 will cause movement of the two gripper devices towards one another; contraction of the jack will move them away from each other.

The carriage 15 is movable along the runners 14 between a sack receiving station, which it is shown occupying in FIG. '2, and a sack filling station (FIGS. 3 and 5). Movement of the carriage is powered by a pneumatic jack 26 mounted on the apparatus frame and having its rod connected to the carriage 15 by lever arms 27 and 28 pivotally mounted at 29. In an alternative arrangement to that shown the jack 26 could be mounted at a lower level than the carriage 15, at the upstream end of the framework 11 and the lever assembly connecting the jack to the carriage arranged for movement in a vertical rather than a horizontal plane.

A posser 30 (FIG. 5) is situated immediately below the sack filling station and comprises a vibrator acting on a platform 31 formed by the upper run of an endless conveyor. The level of the posser platform 31 is adjustable under the control of a pneumatic jack 32, between a lowered position shown in full lines in FIG. 5 and a raised position shown in dot and dash lines in which the platform surface is level with the surface of a further endless conveyor 33.

A pair of co-operating endless chains 34 and 35 (FIG. 2) are mounted in cantilever fashion so as to extend upstream into the sack filling station already referred to, and are drivable in unison in the direction of the arrows by an electric motor 36. At their downstream ends the supports 37 and 38 for the respective chains 34 and 35 are rotatably mounted on axes 39 and 40. A lever 41 rotatable about axis 39 and secured to the mounting of endless chain 34 is pivotable about such axis by means of a pneumatic jack 42. The free end of the lever 41 is formed as a toothed quadrant meshing with a similar quadrant 43 mounted for rotation about axis 40 and secured to the mounting of endless chain 35. The endless chains 34 and 35 are thus movable in concert, by operation of the jack 42, between a mutually spaced condition shown in FIG. 2 and an engaged condition (FIG. 3) in which the chains co-operate to grip therebetween a sack along its top edge and to convey it downstream, i.e. from right to left as seen in FIGS. 2 and 3.

A further pair of co-operating endless chains, one of which is visible at 44 in FIG. 5, is mounted immediately downstream of the chains 34 and 35 to take over the con veyance of sacks from the latter chains and to move them through a sewing mechanism indicated generally at 45 in FIGS. 3 and 5; the sewing mechanism is of conventional construction and will not be described. The chains 44 are driven in unison by an electric motor 46.

The sequence of operations of the above described apparatus to fill a sack will now be described. Although the inter-relation of the controls for operating the various elements of the apparatus entirely automatically in the correct sequence and for the appropriate periods of time will not be described in any detail it will be clear to those skilled in the art that such operations may be initiated and inter-related in the manner to be described under electrical control by the operation of conventional microswitches actuated by the movements of the various elements.

Assuming a stack of sacks to be present at the downstream end of the conveyor 9, where the position of such stack is located by a transverse barrier 47 (FIGS. 2 and 3), the sequence of operations commences with the expansion of jack 4 to move the suction cup 6 downwardly from its position shown in full lines until the suction cup engages the topmost sack near to the mouth end thereof. The suction is then immediately effective to grip the sack and the jack 4 contracts to return the suction cup 6 to its full line position, bringing the mouth end of the sack with it.

The jack 7 now expands to swing the arm 2 about its pivot 3 into the position shown in dot and dash lines in FIG. 1; the sack is thus lifted, mouth upwards, and its mouth end passes into the guide shoe 10 to be positively located thereby with the body of the sack hanging downwardly. During this lifting of the sack the pack 26 has expanded to move the carriage 15 upstream to the said receiving station, i.e. to its FIG. 2 position.

The jack 22 now expands to close the gripper devices 17-18, which grip the topmost corners of the sack in the region of its gussetts.

The jack 13 now expands and suction in the suction cup 12 is thereby automatically applied. The suction cup 12 moves inwardly and engages and grips the sack wall near to its mouth immediately opposite the suction cup 6. The sack now being gripped at two opposite points by the suction cups 6 and 12, as well as by the gripper devices 17-18, the jacks 5 and 13 now contract and the jack 23 simultaneously expands so that the suction cups move away from one another to draw the sack mouth open and the gripper devices simultaneously swing inwardly towards one another to accommodate such opening movement. With the mouth of the sack now open the jack 20 contracts to lower the filling spout into the sack mouth, and as soon as the sack and the filling spout are properly engaged with one another the suction in the cups 6 and 12 is automatically interrupted so that the sack is released therefrom.

The jack 26 now contracts to move the carriage 15, carrying the empty sack, downstream to the sack filling station where the filling spout 16 on the carriage becomes aligned beneath the outlet 48 of a hopper containing the commodity with which the sack is to be filled. At the same time the sack comes to rest immediately above the posser platform 31.

Material is now fed from the hopper into the sack via the filling spout 16 and at the same time the jack 32 graduallyexpands so as to raise the vibrating posser platform as the sack is filled. The sack is thereby possed and at the same time the weight of its increasing contents is supported by the posser rather than by the gripper devices 17-18. During filling, the jack and 7 contract to return the sack lifting means to its rest position.

Filling of the sack being completed the jack expands to raise the filling spout out of the bag mouth to its position shown in dot and dash lines in FIG. 4. The jack 23 now contracts to spread the gripper devices 17-18 apart so as to extend, and thereby close, the mouth of the sack.

The jack 42 now expands so as to close together the endless chains 34 and to grip the sack therebetween just below the intended sewing adjacent its top edge. The chains themselves are stationary at this time; as soon as they have come together, however, the jack 22 contracts to separate the gripper members 17 and 18 and thus release the top corners of the sack which is now held upright by the grip of endless chains 34 and 35. Drive is now transmitted to the chains and at the same time drive is transmitted to the endless conveyor constituting the posser platform 31 so that the sack is conveyed downstream by the action of chains 34 and 35 and the posser conveyor. Conveyance of the sack is shortly taken over by the chains 44 and the endless conveyor 33 and it is moved through the sewing mechanism where its mouth is sealed, and thence out of the apparatus. As the sack moves through the sewing head the jack 26 expands to withdraw the carriage 15 to the sack receiving station, the jack 32 contracts to lower the posser 30, and the jack 42 contracts to spread the endless chains 34- and 35; thus the apparatus is made ready to receive the next sack to be filled.

Referring now to FIGS. 6 and 7 of the drawings, in the modification illustrated therein the single pair of suction cups of the apparatus described above is replaced by two suction devices each comprising three suction cups, the cups to 52 replacing the cup 6 of the lifting device .and the cups 53 to '55 replacing the cup 12. The cup 51 is connected to the jack 5 on the swinging arm 2 in a similar manner to the cup 6, whilst the cup 54 is connected to the jack 13 in the same way as the cup 12. Flexible metal plates 56 and 57 inter-connect the cups of each group of three and thus serve to support the outer pairs of cups 50, 52 and 53, 55, which outer cups are con- 4 nected into the main vacuum lines by means of flexible tubes '58.

In the position of the apparatus illustrated in FIG. 6 a sack 8 has been picked up from the top of the stack by the three suction cups 50 to '52 and lifted through the guide shoe 10 into the mouth opening position, where its top corners have been gripped by the gripper members 17-18 and the three suction cups 53 to 55 have moved in under the control of the jack 13 to engage the sack; it will be noted that in this relative position of the two suction devices the six suction cups are disposed in three axially aligned pairs.

The jacks 5 and 13 now contracts so as positively to draw the two central suction cups 51 and 54 apart and, via the latter and the flexible metal plates 56 and 57, similarly to withdraw the outer pairs of cups. At first the two opposite sides of the mouth of the sack are drawn apart in parallelism, as the gripper members 17-18 move inwardly, until a point is reached at which the opposite ends of the plates 56 and 57 engage with respective stops 59 mounted on the main frame of the apparatus so that the flexible plates are urged into the curved configurations shown in FIG. 7 as the jacks 5 and 13 continue to contract. FIG. 7 shows the final positions reached by the suction devices when the mouth of the sack has been opened to its desired extent, and it will be observed that the mouth is now held in an oval configuration for the entry of the filling spout thereinto.

The mouths of the suction cups are preferably provided with wire mesh closures to prevent the wall of the sack being sucked into the cups to an undesirable extent.

It will thus be seen that in its above described form the invention provides improved apparatus whereby sacks, bags and like containers may be filled with all manner of commodities entirely automatically, and in a speedy and reliable manner in which only a minimum of supervision of the apparatus is required.

We claim:

1. Apparatus for use in the filling of flexible sacks or bags, comprising in combination:

a carriage mounted for movement between a sack or bag receiving and opening station and a sack or bag filling station;

a filling spout movable with said carriage;

a pair of gripper devices carried by said carriage and operable to grip a sack or bag adjacent its mouth at two substantially opposite regions thereof, such gripper devices being movable towards and away from one another so as respectively to enable the mouth of the sack or bag to be opened and to close the same once it has been filled;

lifting means operable to lift each sack or bag into said receiving and opening station for engagement by said gripper devices;

suction means operable at said receiving and opening station to open the mouth of the sack or bag at said receiving and opening station in conjunction with the movement of said gripper devices towards one another;

means operable to bring about relative movement between the sack or bag and the said filling spout, prior to the release of the sack or bag by the said suction means, to engage the open mouth of the sack or bag with the spout;

drive means for transferring each filled sack or bag from the said filling station to mouth sealing means, said drive means including a pair of endless drive elements extending into the said filling station and mounted for opening and closing movement relative to one another so as to be open during the filling step but to be closable together to grip the mouth of the filled sack or bag therebetween prior to its release from the said gripper devices;

and means arranged to provide underneath support for each sack or bag both at the said filling station and during the transfer of the sack or bag to said mouth sealing means.

2. Apparatus according to claim 1, wherein the said suction means comprises a pair of suction devices adapted to engage the sack or bag on opposite sides thereof in the region of its mouth and relatively movable away from one another to draw the mouth open.

3. Apparatus according to claim 2, wherein one of the said suction devices is associated with the said lifting means so as to constitute the means whereby the said lifting means grips the sack or bag to lift it.

4. Apparatus according to claim 3, wherein the other suction device is mounted at the said receiving and opening station so as to be engageable with the sack or bag on the side thereof opposite from that where it is already gripped by the first-mentioned suction device, once the sack or bag has been lifted.

5. Apparatus according to claim 3, including means for supporting a stack of sacks or bags to be filled, and wherein the said lifting means comprises an arm carrying a suction device and swingable about a pivotal mounting to pick up sacks or bags one by one from the top of such a stack and lift them.

6. Apparatus according to claim 2, wherein each of said suction devices comprises a single suction cup, the arrangement being such that said cups are disposed on a common axis and positioned to engage the mouth of a sack or bag substantially centrally of its width when in 9 their relative positions for opening the mouth of the sack or bag.

7. Apparatus according to claim 2, wherein each of said suction devices comprises two or more suction cups, the arrangement being such that the cups of the two devices are disposed in axially aligned cooperating pairs when in their relative positions for opening the mouth of a sack or bag.

8. Apparatus according to claim 7, wherein each of said suction devices comprises three suction cups, the central cooperationg pair of cups being arranged to engage the mouth of a sack or bag substantially centrally of its width while the two outer cooperating pairs of cups are arranged to engage the mouth of a sack or bag one on each side of said central cooperating pair.

9. Apparatus according to claim 8, wherein the two outer suction cups of each suction device are connected to the central cup thereof via flexible connections.

10. Apparatus according to claim 9, wherein the said flexible connections between the two outer suction cups and the central suction cup include one or more flexible mounting plates for the outer suction cups, said flexible plate or plates extending outwardly beyond said outer suction cups and being engageable with stop members of the apparatus when the two suction devices are moved relative to one another to open the mouth of a sack or bag, so as by fiexure of said mounting plates to cause the sack or bag mouth to be opened to a substantially circular or oval configuration.

11. Apparatus according to claim 1, including a guide shoe arranged to receive the mouth of the sack or bag as it is lifted into the said receiving and opening station, such guide shoe being arranged to define the position of the mouth of the sack or bag for opening by the said suction means.

12. Apparatus according to claim 1, wherein the said filling spout is carried by the said carriage and is arranged to receive material from a storage hopper or the like at said bag filling station for passage into a sack or bag to be filled.

13. Apparatus according to claim 12, wherein the said filling spout is movable relatively to the carriage so as to be insertable in and withdrawable from the open mouth of a sack or bag held by the said gripper devices, whereby to hold the mouth of the sack or bag open for filling.

14. Apparatus according to claim 13, wherein the said filling spout is arranged to be engaged with each sack or 10 bag when the carriage is at the said receiving and openmg statlon but is at that time displaced from the outlet from a storage hopper or the like for the commodity with which the sacks or bags are to be filled, the said filling spout being arranged to be aligned with said outlet when the carriage is at the said filling station.

15. Apparatus according to claim 1, wherein the said underneath support means includes a vibratory posser situated so that each sack or bag will sit on a vibrating platform thereof while it is being filled.

16. Apparatus according to claim 15, wherein the said posser is mounted for vertical movement so that it may be caused to rise and thus lift the bottom of the sack or bag during filling.

17. Apparatus according to claim 15, wherein the vibratory platform of the said posser is constituted by an endless conveyor.

18. Apparatus according to claim 15, wherein the said underneath support means further comprises endless conveyor means extending from the said posser to said mouth sealing means.

19. Apparatus according to claim 1, wherein the said drive means includes at least one further cooperating pair of endless drive elements downstream of that pair already mentioned, to take over the movement of each sack or bag from the first pair of drive elements.

20. Apparatus according to claim 1, wherein the said drive elements comprise endless chains.

References Cited UNITED STATES PATENTS 2,853,842 9/1958 Vredenburg 53-126X 2,899,783 8/1959 Otto 53126X 2,996,858 8/1961 Swenson 53-126X 2,684,191 7/1954 Dolman 53-488 2,725,168 11/1965 Lindstaedt et al. 53-188 3,208,194 9/1965 Johnson et al. 53-386X 3,427,780 2/1969 Bock 53-386X 3,430,409 3/1969 Manfredonia et a1. 53-386X T'RAVIS S. MCGlEHEE, Primary Examiner H. M. 'CULVER, Assistant Examiner US. Cl. XJR. 53190, 386 

